3 Pages in Charles Darwin's Library associated with "mental states - discontent"

The anatomy and philosophy of expression.
By: Bell, Charles.
Publication info: London :John Murray,1844.
Pages: Page 140 Page 150
Mécanisme de la physionomie humaine, ou analyse électro-physiologique de l'expression des passions.
By: Duchenne, G.-B. (Guillaume-Benjamin),
Publication info: Paris :Jules Renouard,1862.
Pages: Page 91